Spending on television ads in the race for Indiana's open Senate seat between Republican Richard Mourdock and Democrat Joe Donnelly topped $25 million this week, nearly five times what was spent in the 2010 Indiana Senate race.

A Democrat tracking ad buys for the Donnelly campaign said Wednesday that Mourdock and his supporters had bought $13.6 million of air time through Election Day and Donnelly supporters had logged $11.5 million. The person spoke on condition of anonymity because the campaign doesn't publicly release tallies.

Indiana's Senate race was already on its way to being the most expensive the state has seen, well more than the close to $6 million spent between Republican U.S. Sen. Dan Coats and then-Democratic U.S. Rep. Brad Ellsworth. But Mourdock's high-profile comment about rape and abortion in last week's debate spurred Democrats and Republicans to buy even more commercial time.

The Democratic Senatorial Campaign Committee spent $1.1 million replaying Mourdock's comments in an ad that began airing last week. In return, American Crossroads spent $1.5 million this week to push the narrative back against Donnelly, as Republicans attempt to re-inject President Barack Obama into the Senate battle.

"After voting for Barack Obama's agenda, Donnelly wants us to give him a promotion," the narrator says in the new spot.

Mourdock, his campaign staff, and national Republicans swept into the fallout from after the debate have insisted voters are no longer talking about the abortion comment. Donnelly and Democratic groups, meanwhile, have done everything they can to make sure the comment doesn't disappear.

Democratic super PAC American Bridge, for instance, is spending $30,000 to send talking mailers to Indiana residents that replay Mourdock's comment to potential voters. Spokesman Matt Thornton says it's meant to alert voters to Mourdock's "extreme" positions even though Donnelly's position on abortion was the same as Mourdock's until recently and is still quite similar.

Democrats are doing what they can to remind voters of Mourdock's remark, while Republicans try to refocus the race on Donnelly's support for the federal health care law and the auto bailout.

The Mourdock campaign has accused Democrats of being "sleazy" when talking about the comments.

Democratic and Republican internal polls taken since Mourdock made the comment have all shown a race that had been at a stalemate since the May primary beginning to break slightly for Donnelly.

Throughout the race, the Donnelly and Mourdock campaigns have played an almost marginal role on air compared with the roughly $20 million spent by outside groups. Crossroads GPS is by far the biggest spender in Indiana, at close to $5 million, but is not necessarily the most widespread player. That's because broadcast rules allow stations to charge outside groups more for a spot than they charge candidates.

While the air war continues, more groups began spending on mailers, as voters pay more attention to the battle in the final days of the race.